Evaluation of the reproducibility of non-verbal facial expressions in normal persons using dynamic stereophotogrammetric system / 北京大学学报(医学版)

OBJECTIVE@#To assess the reproducibility of non-verbal facial expressions (smile lips closed, smile lips open, lip purse, cheek puff) in normal persons using dynamic three-dimensional (3D) imaging and provide reference data for future research.@*METHODS@#In this study, 15 adults (7 males and 8 females) without facial asymmetry and facial nerve dysfunction were recruited. Each participant was seated upright in front of the 3D imaging system in natural head position. The whole face could be captured in all six cameras. The dynamic 3D system captured 60 3D images per second. Four facial expressions were included: smile lips closed, smile lips open, lip purse, and cheek puff. Before starting, we instructed the subjects to make facial expressions to develop muscle memory. During recording, each facial expression took about 3 to 4 seconds. At least 1 week later, the procedure was repeated. The rest position (T0) was considered as the base frame. The first quartile of expressions (T1), just after reaching the maximum state of expressions (T2), just before the end of maximum state of expressions (T3), the third quartile of expressions (T4), and the end of motion (T5) were selected as key frames. Using the stable part of face such as forehead, each key frame (T1-T5) of the different expressions was aligned on the corresponding frame at rest (T0). The root mean square (RMS) between each key frame and its corresponding frame at rest were calculated. The Wilcoxon signed ranks test was applied to assess statistical differences between the corresponding frames of the different facial expressions.@*RESULTS@#Facial expressions like smile lips closed, smile lips open, and cheek puff were reproducible. Lip purse was not reproducible. The statistically significant differences were found on the T2 frame of the repeated lip purse movement.@*CONCLUSION@#The dynamic 3D imaging can be used to evaluate the reproducibility of facial expressions. Compared with the qualitative analysis and two-dimensions analysis, dynamic 3D images can be able to more truly represent the facial expressions which make the research more reliable.

Evaluation of mandibular stability and condylar volume after orthognathic surgery in patients with severe temporomandibular joint osteoarthrosis / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effect of preoperative condylar condition for mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis on the stability of the jaw after orthognathic surgery and on the postoperative condylar volume changes.@*METHODS@#In this retrospective study, from 2014 to 2019, 37 patients including 1 male and 36 female, aged between 21 to 34 years old with an average age of (28.03±6.52) years, were diagnosed with mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis by Peking University School and Hospital of Stomatology and received orthognathic surgery, meeting the inclusion criteria were included. According to the preoperative condylar condition. There were divided into smooth group and non-smooth group, the lateral cephalometric films 1 week (T0), 3 months (T1), 6 months (T2) and 1 year (T3) after surgery were used to establish the coordinate system and cephalometric analysis to determine the stability of the jaw after operation. The three-dimensional model of the condyle was segmented by cone beam computed tomography (CBCT) 1 week (T0), 3 months (T1), 6 months (T2) and 1 year (T3) after surgery and the volume was obtained to evaluate the change of the condyle volume after surgery. CBCT image data was used to evaluate the changes of the condylar condition after surgery, and to clarify the correlation between the postoperative condylar condition and jaw stability. SPSS 20.0 statistical software was used for statistical analysis, Fisher's exact probability methods were used to compare whether there were statistically significant differences in the stability of the mandibular joint at stages T1, T2 and T3 with different preoperative condylar condition.Spearman correlation coefficient analysis and Mann-Whitney test were used to compare whether there were statistically significant differences in the volume changes at stages T1, T2 and T3 after surgery between the two groups.@*RESULTS@#The recurrence rates of the mandible in the condylar smooth group were T1 36.85%, T2 47.37% and T3 42.11%, respectively. The recurrence rates in the non-smooth condylar group were T1 27.78%, T2 44.44% and T3 55.56%, respectively. There was no statistical difference in the recurrence rates between the two groups at different time points. There was no significant difference in the condylar volume change between smooth group and non-smooth group.@*CONCLUSION@#For patients with mandible retrognathism deformities with severe temporomandibular joint osteoarthrosis and no significant changes in the condyle observed for one year before surgery, there is no difference in the influence of the preoperative condylar condition on the stability of jaw after operation, and no definite influence on the volume of the condyle after operation. Condylar resorption 3 months after surgery can cause instability of the jaw after orthognathic surgery.

Feasibility of Delaire cephalometric analysis to predict the ideal sagittal position of the maxilla and chin for surgery-first patients in orthognathic surgery / 北京大学学报(医学版)

OBJECTIVE@#There is no universally accepted method for determining the ideal sagittal position of the maxilla in orthognathic surgery. The purpose of this study was to compare how well the Delaire's cephalometric analysis correlated with postoperatively findings in patients who underwent orthognathic surgery planned using other cephalometric analyses, as well as to evaluate the feasibility of the Delaire's cephalometric analysis in predicting the ideal sagittal position of the maxilla and chin.@*METHODS@#In the study, 35 patients with skeletal Class III malocclusion were involved and met the criteria. Treatment plans were developed using photographs, 3-D photographs, radiographs, and standard cephalometric measurements. The Delaire's cephalometric analysis data, like the phase measurements (∠C1-L1 and ∠C1-L2) of the sagittal positions of the maxillary and the chin separating the reference line (L1) of NP point and the reference line (L2) of Me point, were analyzed using Dolphin Imaging software. At the same time, the analyses on standard measurements were also performed. Four orthognathic doctors, 4 orthodontic doctors and 4 college students from non-medical majors were selected as aesthetic evaluators to assess the patients' profile aesthetic by visual analogue scale (VAS). The results through the Delaire's cephalometric analysis were statistically compared with that through standard methods.@*RESULTS@#The mean of ∠C1-L1 was 83.93°±2.99° and∠C1-L2 was 89.08° ±2.48° for males postoperatively, and 85.67° ±3.60° and 88.30° ±4.20° for females postoperatively. Compared with the reference values of Chinese goodlooking people, there was no significant difference of NP point, whereas there was a significant difference of Me point. The postoperative aesthetic scores were: the mean was 6.71±0.25 of upper jaws, 6.81±0.30 of chins and 6.90±0.29 of the overall for males; and 7.19±0.22, 7.26±0.34 and 7.39±0.29 for females. Compared with preoperative scores, there was a significant improvement. Furthermore, the scores of chins and the overall scores were related to the sagittal position of the chins.@*CONCLUSION@#Compared with standard cephalometric analysis, the Deliare's cephalometric analysis well unravel the preoperative deformity and the final esthetic sagittal positions of maxillary and chin in the present sample, and could be a useful tool for the planning of surgery-first approach in orthognathic surgery.

Establishment of three-dimensional measurement methods of nasolabial soft tissue for patients with maxillary protrusion / 北京大学学报(医学版)

OBJECTIVE@#To establish a series of three-dimensional measurement methods of nasolabial soft tissue for maxillary protrusion patients by using 3dMD camera, and to evaluate preoperative and postoperative changes of the nasolabial soft tissue.@*METHODS@#Three-dimensional facial photos of 30 female patients with maxillary protrusion [average age, (27.33±2.54) years] were taken by 3dMD camera preoperatively and at the end of postoperative 6 months or more. Then, 3dMD patient software was used to locate the selected landmarks at nasolabial region on the three-dimensional photos. Ten measurements, including soft tissue line distance, angle, curve distance and postoperative three-dimensional volume changes were measured twice with one week interval by 3 investigators, respectively. A standard consistency test calculated by the correlation coefficients (ICC) was performed between two sets of data (including all of the 10 measurements) for each investigator and among the three investigators to verify the repeatability.@*RESULTS@#The average maxillary incisor retraction distance of the 30 subjects was (5.13±0.99) mm, and the average follow-up time was (11.07±5.11) months. The standard consistency test was performed between the two sets of data for each investigator, and the correlation coefficients (ICC) of the 10 measurements were all over 0.8 for each investigator (P>0.05). The standard consistency test was performed among the three surveyors, with the result that the ICC of the width of the bilateral inner canthus, the height of the nose, the height of nasal tip, nasolabial angle, philtrum length, the curve height of upper vermilion and the height of upper lip were greater than 0.8 (P>0.05), and the ICC of the distance between SbalSbal, length of nasal dorsum and three-dimensional volume change of upper lip were 0.680, 0.627 and 0.528, respectively (P>0.05).@*CONCLUSION@#3dMD camera and 3dMD patient software can be used to measure and analyze the three-dimensional morphology of the nasolabial soft tissue for patients with maxillary protrusion preoperatively and postoperatively, and it is relatively accurate and reliable. However, the repeatability of three-dimensional positioning of the nasal tip point and the Sbal is slightly worse resulting in the lower value of the ICC of the distance between SbalSbal and length of nasal dorsum, as well as the upper lip three-dimensional volume change after the operation.

Accuracy analysis of computer assisted navigation for condylectomy via intraoral approach / 北京大学学报(医学版)

OBJECTIVE@#To explore the application accuracy of virtual preoperative plan after the condylectomy via intraoral approach under computer assisted surgical navigation, and to analyze the location and cause of the surgical deviation to provide reference for the surgical procedure improvement in the future.@*METHODS@#In the study, 23 cases with condylar hypertrophy (11 with condylar osteochondroma and 12 with condylar benign hypertrophy) in Department of Oral and Maxilloficial Surgery, Peking University School and Hospital of Atomatology from December 2012 to December 2016 were treated by condylectomy via intraoral approach under computer assisted surgical navigation. The patient's spiral CT data were imported into ProPlan software before operation, and the affected mandibular ramus was reconstructed three-dimensionally. The condylar osteotomy line was designed according to the lesion range, and the preoperative design model was generated and introduced into the BrainLab navigation system. Under the guidance of computer navigation, the intraoral approach was used to complete the condylar resection according to the preoperative design of the osteotomy line. Cranial spiral CT of the craniofacial region was taken within one week after operation. three-dimensional reconstruction of the mandibular ramus at the condylectomy side was performed, and the condylar section was divided into six segments (anterolateral, anterior, anteromedial, posteromedial, posterior, and posterolateral) and the corresponding regional measurement points P1 to P6 were defined. Then the preoperative virtual model and the postoperative actual model were matched by Geomagic studio 12.0 to compare the differences and to analyze the accuracy of the operation.@*RESULTS@#All the patients had successfully accomplished the operation and obtained satisfactory results. Postoperative CT showed that the condyle lesion was completely resected, and the condylar osteotomy line was basically consistent with the surgical design. No tumor recurrence or temporomandibular joint ankylosis during the follow-up period. The postoperative accuracy analysis of the condylar resection showed that the confidence intervals measured by the six groups of P1 to P6 were (-2.26 mm, -1.89 mm), (-2.30 mm, -1.45 mm), (-3.37 mm, -2.91 mm), (-2.83 mm, -1.75 mm), (-1.13 mm, 0.99 mm), and(-1.17 mm, 0.17 mm), where P3 group was different from the other 5 groups. There was no significant difference between the P5 and P6 groups and the difference between the other four groups was statistically significant.@*CONCLUSION@#Under the guidance of computer navigation, the intraoral approach can be performed more accurately. The surgical deviation of each part of the osteotomy surface is mainly due to excessive resection. The anterior medial area of the anterior medial condyle represents the most excessive resection. The posterior and posterior lateral measurement points represent the posterior condylar area. The average deviation is not large, but the fluctuation of the deviation value is larger than that of the other four groups. The accuracy of computer-assisted subtotal resection has yet to be improved.

Evaluation of accuracy of virtual occlusal definition in Angle class I molar relationship / 北京大学学报(医学版)

OBJECTIVE@#To evaluate the accuracy of virtual occlusal definition in non-Angle class I molar relationship, and to evaluate the clinical feasibility.@*METHODS@#Twenty pairs of models of orthognathic patients were included in this study. The inclusion criteria were: (1) finished with pre-surgical orthodontic treatment and (2) stable final occlusion. The exclusion criteria were: (1) existence of distorted teeth, (2) needs for segmentation, (3) defect of dentition except for orthodontic extraction ones, and (4) existence of tooth space. The tooth-extracted test group included 10 models with two premolars extracted during preoperative orthodontic treatment. Their molar relationships were not Angle class I relationship. The non-tooth-extracted test group included another 10 models without teeth extracted, therefore their molar relationships were Angle class I. To define the final occlusion in virtual environment, two steps were included: (1) The morphology data of upper and lower dentition were digitalized by surface scanner (Smart Optics/Activity 102; Model-Tray GmbH, Hamburg, Germany); (2) the virtual relationships were defined using 3Shape software. The control standard of final occlusion was manually defined using gypsum models and then digitalized by surface scanner. The final occlusion of test group and control standard were overlapped according to lower dentition morphology. Errors were evaluated by calculating the distance between the corresponding reference points of testing group and control standard locations.@*RESULTS@#The overall errors for upper dentition between test group and control standard location were (0.51±0.18) mm in non-tooth-extracted test group and (0.60±0.36) mm in tooth-extracted test group. The errors were significantly different between these two test groups (P<0.05). However, in both test groups, the errors of each tooth in a single dentition does not differ from one another. There was no significant difference between errors in tooth-extracted test group and 1 mm (P>0.05); and the accuracy of non-tooth-extracted group was significantly smaller than 1 mm (P<0.05).@*CONCLUSION@#The error of virtual occlusal definition of none class I molar relationship is higher than that of class I relationship, with an accuracy of 1 mm. However, its accuracy is still feasible for clinical application.

Comparative analysis of two surgical techniques for controlling nasal width after Le Fort I osteotomy / 中华整形外科杂志

<p><b>OBJECTIVE</b>To compare the efficacy of two surgical techniques for controllong nasal width after Le Fort I osteotomy.</p><p><b>METHODS</b>Fifty-five patients who received the Le Fort I osteotomy have been included in this study. They were randomly divided into 2 groups. The experimental group received extraoral ABS, and the control group received traditional intraoral ABS. 3D photos of the patient's face were taken before operation and at postoperative 3 months. Alar width was measured on the 3D photos. Data was reported as means and standard deviations, and statistic analysis was done by using student t test.</p><p><b>RESULTS</b>Compared with presurgical data, G. lat-G. lat increased by (2.66 +/- 1.47) mm, Al-Al increased by (2.20 +/- 1.22) mm and Sbal-Sbal increased by (1.30 +/- 1.33) mm in experimental group. G. lat-G. lat increased by (1.38 +/- 1.29) mm, Al-Al increased by (1.06 +/- 0.95) mm and Sbal-Sbal increased by (0.36 +/- 1.33) mm in the control group. There was significant difference between two groups.</p><p><b>CONCLUSIONS</b>The surgical technique of ABS is the most important factor for determining the postoperative alar width. Both techniques have better effect on the Sbal-Sbal width control than the G. lat-G. lat and Al-Al width control. Traditional intraoral ABS can more effectively control the alar width. Both techniques cannot completely control the alar base widening after Le Fort I osteotomy.</p>

Clinical application of condylectomy via intraoral approach under computer assisted surgical navigation / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To assess the application of computer assisted surgical navigation in condylectomy via intraoral approach and its clinical results.</p><p><b>METHODS</b>Eight patients aged from 16 to 56 were treated by condylectomy via intraoral approach under computer assisted surgical navigation. There were 6 female and 2 male. The lesions were condyle osteoma in 3 patients, hemimandibular hyperplasia and condylar hyperplasia in 5 patients. Most patients had concomitant LeFortIosteotomy (6 cases), bilateral sagittal split ramus osteotomy (BSSRO) (5 cases),contralateral sagittal split ramus osteotomy (SSRO) (1 cases), genioplasty (4 cases) and mandible contouring (6 cases) to recover the facial symmetry.</p><p><b>RESULTS</b>All patients had good occlusion, oral function and facial symmetry after the operation. The average mouth opening was 38 mm before operation, and 41 mm one month after operation. The temporomandibular joint(TMJ) dysfunction syndrome alleviated or disappeared. The follow-up period was 3-12 months, and results were stable.</p><p><b>CONCLUSIONS</b>Computer assisted surgical navigation can precisely accomplish the condylectomy via intraoral approach.It causes less trauma to the patient than traditional condylectomy, and can better preserve the TMJ structure and function.</p>

The treatment of mandibular micrognathia secondary to temporomandibular joint ankylosis with distraction osteogenesis / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate the clinical effect of distraction osteogenesis for patients with mandibular micrognathia secondary to temporomandibular joint (TMJ) ankylosis.</p><p><b>METHODS</b>43 patients (aged from 2 to 61 years old) with mandibular micrognathia were treated with mandibular distraction osteogenesis. Two types of mechanical distraction were utilized in this study. Ten patients (age ranged from 2 to 16-years-old, mean age 7.6 years old) with severe micrognathia underwent bilateral mandibular distraction with rigid external distraction (RED) device. Other 33 patients were treated with unilateral(6 cases) or bilateral (27 cases) mandibular distraction using internal distraction device. Distraction was started on the 4th to 8th day after operation and distraction rate was 0.25 mm every time, four times a day. Distractor was removed after 3 to 6 months of consolidation period.</p><p><b>RESULTS</b>Eighty sides of mandible in 43 patients were lengthened. The mean distraction distance was 23.2 mm (ranged from 14 to 35 mm). After distraction, the average posterior airway space (PAS) was enlarged from 4.9 mm to 10.4 mm and average angle of sella-nasion-point B (SNB) was increased from 64.2 degrees to 74.5 degrees. The apnea hypopnea index (AHI) was decrease significantly. The profile was improved and OSA was improved effectively in each patient. No complication occurred during treatment. No persistent numbness of lower lip was observed. All patients were satisfied with the results. After a mean follow-up period of 20.3 months(5 to 103 months) , the result was stable and no obvious relapse of micrognathia was observed.</p><p><b>CONCLUSIONS</b>Distraction osteogenesis is an effective way in correction of mandibular micrognathia secondary to TMJ ankylosis. RED is a new method for treatment of children and adolescence with severe mandibular micrognathia. The procedure is simple and safe with stable result.</p>

Preliminary study of condylectomy via intraoral approach / 中华口腔医学杂志

<p><b>OBJECTIVE</b>Condylectomy was performed to treat condylar osteoma or hyperplasia. Introduced two methods of condylectomy via intraoral approach and evaluated their clinical results.</p><p><b>METHODS</b>Thirty-five patients, aging from 22 to 57.21 years, were treated by condylectomy via intraoral approach, of which 21 were condyle osteoma, 14 hemimandibular hyperplasia and condylar hyperplasia. Intraoral vertical ramus osteotomy (IVRO) were used in 32 patients and intraoral condylectomy via coronoid process resection was used in 3 patients.</p><p><b>RESULTS</b>The treatment results including oral function and facial symmetry after the operation were good in all patients. The temporomandibular joint (TMJ) dysfunction syndrome alleviated or disappeared. The follow-up period was 6 months to 3 years, and no relapse of condylar osteoma or hyperplasia was found. The patients who had IVRO and TMJ reconstruction had some degree of transplanted bone resorption, and one patients had relapse of facial deformity. But the patients who had intraoral condylectomy via coronoid process resection only had mild condyle remodeling and no obvious bone resorption was noted.</p><p><b>CONCLUSIONS</b>The two methods of intraoral condylectomy introduced in this stugy can successfully correct the facial deformity and TMJ dysfunction caused by condylar osteoma or hyperplasia. But the surgeons need to have excellent surgical skills and careful selection of the indications.</p>

Mutations analysis of RP1 gene in 110 Chinese with retinitis pigmentosa / 中华实验眼科杂志

Background Retinitis pigmentosa (RP) is a monogenic inheritance and blinding disease of fundus oculi.There is not an effective therapeutic method now.Objective This work was to identify the mutations of RP1 gene in Chinese RP patients in Ningxia area and to explore the potential interactions in the pathogenesis of RP.Methods The periphery blood of 3-5 ml was collected from 110 individuals with RP(35 ADRP and 75SRP)and 100 normal controls in Ningxia area.Polymerase chain reaction (PCR) and direct DNA sequencing were used to screening the sequence alterations in the entire coding region and splice sites of RP1 gene.Multivariate analysis and two web-based programs( PolyPhen and SIFT) were used to analyze the results.Results Eleven mutation locus were detected in the exon 4 of RP1 gene including two novel sequence variants:p.Lys1152Lys without a higher mutation rate in comparison with normal control group(x2 =9.12 P＜0.01 ),but c.* 247A＞C with a higher mutation rate in comparison with normal control group(x2 =12.77,P＜0.01 ) and c.* 247A＞C mutation was thought to be correlated with RP( r=1.11,P＜0.05 ).The other ten mutation locus were reported as single nucleotide polymorphisms (SNP).The mutation rate of p.Gln1725Gln was found to be higher in the RP patients than the normal controls (x2 =42.09,P＜0.01 ),but no the significant correlation was seen between the pathogenesis of RP and mutation of p.Gln1725Gln(r=1.74,P＞0.05).p.Lys1152Lys mutation was found in only 1 patient.Three SNPs( p.Arg872His,Ala1670Thr,Ser1691Pro) were always occurred in the same 83 RP patient and the relevance ratio was higher than controls ( P＜0.01 ).The age of night blindness on patients with concurrent three mutations was (30.54± 13.68 ) years,and the best corrected visual acuity (BCVA) was 0.50 ± 0.38.The age of night blindness on patients without concurrent three mutations was(21.06± 16.24) years,and the BCVA was 0.40 ±0.33 and were higher than controls ( t =2.11,P ＜ 0.05 ).Conclusions In this study,the prevalence of RP1 mutations among the RP patients in Ningxia population was lower than other populations (＜ 1％ ).The alliance of SNPs (p.Arg872His、p.Ala1670Thr、p.Ser1691Pro) may play a protective role on RP patients and reduce the frequency of mutatiaon in RP1 gene.

Surgical management of hemifacial microsomia: a report of 24 cases / 中华整形外科杂志

<p><b>OBJECTIVE</b>To investigate the therapeutic effect of combined treatment for hemifacial microsomia (HFM).</p><p><b>METHODS</b>From July 1991 to August 2006, 24 consecutive patients with HFM were retrospectively analyzed. They underwent orthognathic surgery, free flap transplantation, Medpor implant, distraction osteogenesis. The patients age, deformity type, surgical timing, treatment methods and complications were analyzed.</p><p><b>RESULTS</b>The treatment was completed in all the patients. The facial symmetry was improved dramatically after operation. The occlusion relationship was improved also with good occlusion plane. 8 free flaps were survived with no necrosis.</p><p><b>CONCLUSIONS</b>The surgical treatment should be designed based on the age and deformity type in HFM. The occlusion relationship and appearance can be both improve markedly.</p>

Distraction osteogenesis of the mandibular ramus in hemifacial microsomia / 中华整形外科杂志

<p><b>OBJECTIVE</b>To study the application of distraction osteogenesis (DO) of the mandibular ramus in hemifacial microsomia.</p><p><b>METHODS</b>From 1999 to 2006, 15 patients with hemifacial microsomia were treated with DO of the ramus, including 12 cases of children and juveniles, 3 cases of grown-ups. Maxillary Le Fort I osteotomy, unilateral sagittal split ramus osteotomy, genioplasty and free scapular flaps were selected to perform on the first or secondary stage of treatment.</p><p><b>RESULTS</b>Successful distraction was achieved in all patients with an average distraction distance of 21.25 mm. The distractor was removed after consolidation proved by clinical examination and X-ray. Facial appearance and and occlusal relationship were improved greatly. The occlusal plane was almost normal. There was no infection, malunion or permanent injury of inferior alveolar nerve.</p><p><b>CONCLUSIONS</b>DO of the ramus is very effective for the correction of severe hemifacial microsomia. It has much better therapeutic effect than traditional orthognathic procedures.</p>

Correction of progressive hemifacial atrophy by orthognathic surgical procedures combined distraction osteogenesis and scapular flap transplantation: 5 cases report / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility and the therapeutic effect of orthognathic surgical procedures combined distraction osteogenesis and scapular flap for correction of progressive hemifacial atrophy.</p><p><b>METHODS</b>5 cases with progressive hemifacial atrophy were treated. 1 mild case was treated with microsurgical de-epithelia scapular flap (MDSF) and genioplasty in one stage. The 2 moderate cases were treated with Le Fort 1 osteotomy following by sagittal split ramus osteotomy and genioplasty at the first stage. 3 - 6 months later, the MDSFs were used for augmentation. 2 sever cases were treated with bimaxillary distraction osteogenesis on the affected side. 3 - 4 months later, the distraction devices were removed and MDSFs were transplanted.</p><p><b>RESULTS</b>The facial asymmetry was obviously improved. The orthognathic procedures and distraction osteogenesis achieved good therapeutic effect. All the MDSFs were survived.</p><p><b>CONCLUSIONS</b>The progressive hemifacial atrophy can result in very severe deformity when it occurs in very young age. The combined deformity of bone and soft tissue can be effectively corrected by orthognathic procedures combined with distraction osteogenesis and scapular flap transplantation.</p>

Prophylactic administration of Yunnan Baiyao capsule reduces intra-operative blood loss in orthognathic surgery / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the haemostatic efficacy and safety of prophylactic oral administration of Yunan Baiyao capsules on reduction of blood loss in bimaxillary orthognathic surgery.</p><p><b>METHODS</b>Eighty-seven patients scheduled for Le Fort I osteotomy and bilateral sagittal split ramus osteotomy (BSSRO) were enrolled in the prospective, randomized, double-blind, placebo-controlled clinical study. Forty-three patients took prophylactic oral administration of Yunnan Baiyao capsules 3 days before operation, and 44 patients without Yunnan Baiyao administration served as control. The intraoperative blood loss during Le Fort I osteotomy and bilateral sagittal split ramus osteotomy was estimated and the safety of Yunnan Baiyao capsules was evaluated.</p><p><b>RESULTS</b>The total blood loss in the Yunnan Baiyao group (330.5 +/- 134.4) ml was significantly lower than that of the control group (420.3 +/- 175.9) ml. The blood loss of Le Fort I osteotomy in the Yunnan Baiyao group (154.9 +/- 84.3) ml was also significantly lower than that of the control group (203.8 +/- 98.1) ml. The mean blood loss of BSSRO in the Yunnan Baiyao group was also lower than that of the control group, but the differences was not significant. The post-operative fibrinolysis was in the same level in both groups. Thromboemblic events or other side effects were not observed in this clinical trial.</p><p><b>CONCLUSIONS</b>Prophylactic oral administration of Yunnan Baiyao capsules can effectively reduce the intra-operative blood loss in bimaxillary orthognathic surgery. Yunnan Baiyao capsule are an effective and safe haemostatic traditional Chinese medicine.</p>

Treatment of severe micrognathia accompanying obstructive sleep apnea hypopnea syndrome with rigid external distractor / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To approach the treatment of severe micrognathia accompanying obstructive sleep apnea hypopnea syndrome (OSAHS) with rigid external distractor (RED) in children.</p><p><b>METHODS</b>Six cases patients (4 males, 2 females) aged between 1.5 and 14 years, were diagnosed as ankylosis of temporomandibular joint severe micrognathia, and OSAHS. Under the nasal intubation and general anesthesia, the surgical procedures were performed by submandibular approach and osteotomy was done in mandible body. Mini plate was fixed and connected to RED. The distraction procedure was carried out</p><p><b>RESULTS</b>Patients' profile, posterior airway space, and the results of polysomnography were improved significantly. There were no complications. Four months after removing the RED, the new bone was well formed.</p><p><b>CONCLUSIONS</b>RED technique has advantages of uncomplicated procedures, high quality of new bone formation, and accurate regulation in the treatment of micrognathia. It is especially suitable for the treatment of children with severe micrognathia whose mandibular body is too small to insert the internal distractor.</p>

Orthognathic surgery and distraction osteogenesis for treatment of obstructive sleep apnea hypopnea syndrome / 中国医学科学院学报

<p><b>OBJECTIVE</b>To discuss the indication and protocol of surgical therapy when treating mandibular micrognathism accompanying obstructive sleep apnea-hypopnea syndrome (OSAHS) using distraction osteogenesis and orthognathic surgery.</p><p><b>METHODS</b>A total of 17 patients with mandibular micrognathism accompanying moderate to severe OSAHS, aged 11 to 59 years, 15 men and 2 women, were reviewed. Four of them were treated with orthognathic surgery, 5 of them were treated with distraction osteogenesis, and the other 8 patients were treated with an integrated procedure combining distraction osteogenesis with orthognathic surgery. Cephalometric analysis and polysomnography studies were obtained pre- and postoperatively.</p><p><b>RESULTS</b>SNB angle changed from 64.6 degrees to 71.9 degrees, post airway space (PAS) from 5.4mm to 13.2 mm, apnea and hypopnea index (AHI) from 58.4 to 7.6, lowest saturation of oxygen (LSAT) from 66% to 87%. All the differences showed statistical significance (P < 0.001). The average mental horizontal advancement (MHA) was 14.3 mm and its correlation coefficients with deltaSNB, deltaPAS, deltaAHI, and deltaLSAT were 0.36, 0.62, 0.34, and -0.14, respectively.</p><p><b>CONCLUSIONS</b>Both distraction osteogenesis and orthognathic surgery can be effectively used to treat patients with mandibular micrognathism accompanying OSAHS with slightly different indications. A combination of these two operations may be preferred.</p>

The transformation of fibroblast-like cells originating from different tissue into osteoblasts / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To discuss whether fibroblast-like cells can transform into osteoblasts under specific condition during distraction osteogenesis.</p><p><b>METHODS</b>Fibroblast-like cells were cultured in vitro. BMP-2, TGF-beta(1), BMP-2 and TGF-beta(1) were added into the medium, and the cellular change were observed by histochemistry and immunohistochemistry methods. The distraction was given on the membrane of fibroblast-like cells, and the cellular change were observed under the distraction.</p><p><b>RESULTS</b>fibroblast-like cells from the joint could transform into osteoblasts under the effect of BMP-2 or BMP-2 with TGF-beta(1). Fibroblast-like cells from other regions could not transform into osteoblasts.</p><p><b>CONCLUSION</b>The osteoblasts during distraction osteogenesis are multi-origin.</p>

The effect of platelet-rich plasma on the distraction osteogenesis / 中华整形外科杂志

<p><b>OBJECTIVE</b>To observe the effect of the platelet-rich plasma (PRP) on osteogenesis during bone distraction.</p><p><b>METHODS</b>The osteoblasts were cultured in vitro. The rabbits were used as the animal model of distraction osteogenesis. The proliferation of osteoblasts was analysed through MTT methods. The osteogenesis was observed by histochemical and histoimmunochemical methods.</p><p><b>RESULTS</b>PRP stimulated the proliferation of osteoblasts and facilitated distraction osteogenesis.</p><p><b>CONCLUSIONS</b>PRP could accelerate the osteogenesis during bone distraction. The application of PRP in clinical practice might shorten the period of distraction osteogenesis.</p>